1. Field of the Invention
The present invention relates to hybrid composites including carbon nanotubes and carbide-derived carbon, electron emitters including the hybrid composites, methods of preparing the electron emitters, and electron emission devices including the electron emitters.
2. Description of the Related Art
In general, electron emission devices include electron emitters categorized into hot cathode type electron emitters and cold cathode type electron emitters. Examples of electron emission devices including cold cathode type electron emitters include field emitter array (FEA)-type electron emission devices, surface conduction emitter (SCE)-type electron emission devices, metal insulator metal (MIM)-type electron emission devices, metal insulator semiconductor (MIS)-type electron emission devices, ballistic electron surface emitting (BSE)-type electron emission devices, and the like.
In the electron emission devices described above, the electron emitters that emit electrons may be formed of carbonaceous materials, such as carbon nanotubes, that have excellent conductivity, excellent field enhancement effects, excellent field emission properties, and low work functions.
However, even when carbon nanotubes are vertically oriented in electron emission devices, electron emission may not occur, or electron emission performance may be decreased due to screen effects caused by adjacent carbon nanotubes. Such results may be due to incomplete ohmic contact between the carbon nanotubes and the electrode. In general, carbon nanotubes are shaped into fibers, and such fiber-shaped carbon nanotubes have large field enhancement factors (i). The fiber-shaped materials, however, lack uniformity and lifetime.